In an active-matrix organic light emitting diode (AMOLED), generally there is provided an array substrate and an electroluminescence (EL) substrate. The array substrate provides a drive circuit, which includes a gate driving circuit, a scan driving circuit (Scan GOA), a control circuit (EM GOA), and a pixel driving circuit. The pixel driving circuit is configured to provide an anode voltage for an EL pixel, the gate driving circuit is configured to provide a pixel voltage, a reset (Vi) drive line is configured to provide an anode resetting voltage, and a voltage (Vdd) drive line is configured to provide a pixel driving voltage. A common voltage (Vss) is a cathode input voltage of the EL pixel, etc. In panel resolution, to differentiate EL device problems, device characteristics may be monitored only by means of inline random inspection. However, when it is impossible to inquire inline device characteristics data for panel problems fed back by modules or clients, it is required to further analyze locations where the problems occur so as to further analyze causes of the problems. Therefore, it is urgently needed to test unit circuits to differentiate Array and EL problems or detect EL output current characteristics to provide convenience for resolution.
Furthermore, it is necessary to individually fabricate EL masks (fine metal masks and common metal masks) to shield the effect of the array substrate during EL recipe debugging so as to test EL current output characteristic and debug the structure of the EL device, which increases development costs to a large extent.